21200120237 has 2 divisors, whose sum is σ = 21200120238. Its totient is φ = 21200120236.

The previous prime is 21200120213. The next prime is 21200120239. The reversal of 21200120237 is 73202100212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11684312836 + 9515807401 = 108094^2 + 97549^2 .

It is a cyclic number.

It is not a de Polignac number, because 21200120237 - 2¹² = 21200116141 is a prime.

Together with 21200120239, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21200120239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600060118 + 10600060119.

It is an arithmetic number, because the mean of its divisors is an integer number (10600060119).

Almost surely, 2^21200120237 is an apocalyptic number.

It is an amenable number.

21200120237 is a deficient number, since it is larger than the sum of its proper divisors (1).

21200120237 is an equidigital number, since it uses as much as digits as its factorization.

21200120237 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 336, while the sum is 20.

Adding to 21200120237 its reverse (73202100212), we get a palindrome (94402220449).

The spelling of 21200120237 in words is "twenty-one billion, two hundred million, one hundred twenty thousand, two hundred thirty-seven".